A hi-tech Maglev train capable of 300mph is the best option for a high-speed link between Glasgow and Edinburgh, transport officials have concluded.

The technology, currently only used in Shanghai, China, would mean a trip of just 15 minutes between the cities and is the only cost-effective option available, according to a new report.

A Strathclyde Partnership for Transport (SPT) study into three other possible ways of reducing journey times between Edinburgh and Glasgow has dismissed them as providing little benefit compared with the costs involved.

The report investigated: A new-build track linking the existing network with two new tunnels, one into Edinburgh Waverley and another from Carmyle to Glasgow city centre - reducing travel time to 31 minutes and costing at least £2.4bn.

Upgrading existing line via Shotts; electrifying the route, building a £221m loop and achieving a time of 47 minutes.

Re-alignment of the track at Carstairs junction costing £200m, leading to a time of 46 minutes.

The current time from Queen Street to Waverley is around 50 minutes and officials believe a significant reduction could see it come down to 30 minutes.

After looking at all of them, SPT said the magnetic levitation option should be investigated to provide a new link. The system could be part of a UK high-speed link from London, either travelling north via Manchester in the west or Newcastle in the east.

Alistair Watson, SPT chairman, said: "The conventional options identified in the study, which are lowest cost, only take minutes off the journey time from Glasgow to Edinburgh or involve huge reconstruction costs to get the journey anywhere near 30 minutes.

"With the makers of the Maglev system in the UK claiming their system can go from Glasgow to Edinburgh in 15 minutes, I think it's time to look at that case in detail.

"It appears to me that Maglev could be the most attractive option to emerge from this study. Such a high-speed link between Glasgow and Edinburgh would transform the future growth potential of their economies and of Scotland's economy as a whole."

UK Ultraspeed has a proposal to build a line from Queen Street to Haymarket, running alongside the M8. The technology sees the train levitate above a magnetic track before departure. It hits a speed of more than 100mph after one minute and travels at more than 300mph after four minutes.

One proposal is estimated to cost as much as £200m a year for 30 years in a PPP scheme.

Meanwhile, rail passengers travelling to London from Scotland will be able to arrive earlier and have a faster journey time home in a new timetable to be introduced.

Virgin Trains is to increase frequency on the Glasgow to London route to 13 a day each way, and will operate an early morning train to arrive in the UK capital just after 9am.

The new West Coast Main Line timetable would see the first morning train leaving Glasgow one-and-a-half hours earlier. The fastest journey time would be 15 minutes quicker at four hours and 10 minutes. The timetable is to be introduced in 2009.

Virgin is introducing four additional trains a day on the route in an attempt to compete with airlines on the UK domestic route. Tim Shoveller, Virgin Trains business development director, said: "The train provides city centre to city centre travel without airport transfers and check-in."